Car visor-ready Bluetooth speakerphone solutions offer iPhone users an affordable way to make hands-free calls in vehicles that don't have integrated wireless calling hardware -- in fact, some of the most recent visor accessories pack features that would have been impossible to include in cars only three years ago. Today, we're rounding up four different options from three manufacturers: BlueAnt's S4 ($100), SuperTooth's Buddy ($60) and SuperTooth HD ($129), and Plantronics' K100 ($80). Besides the variations in their prices, each of these units has at least one feature that makes it stand out on paper as a worthwhile option for iPhone users; only one fell below our general recommendation level.

SuperTooth’s two units are substantially different from one another. Buddy is one of the least expensive visor kits we’ve yet tested, while SuperTooth HD is a considerably more ambitious, physically larger, and more complicated design—at more than twice the price. But for a premium unit, and given all that’s inside, it’s actually pretty elegantly designed; SuperTooth is getting better with each new generation of products. Twice as thick as Buddy and wider, it mounts in portrait rather than landscape orientation, with a front-facing microphone hole right before a handsome, illuminated volume dial. A small power button and larger envelope icon button sit below the dial on the mostly glossy black unit, which has a brushed gunmetal metallic plate and a bulging rear speaker grille. Again, a 20 hour talk time battery is included, with 1,000 hours of standby time, this time with a Bluetooth 3.0 chip inside; this is more advanced than what’s in any iPhone today, and downwards-compatible. HD is also capable of announcing the name or number of your caller, plus multi-point pairing, so two phones can be connected to it at once, and you can also use your voice to answer calls.

Where SuperTooth HD really won us over was in sound quality. Due in part to its two integrated speakers, it was the best performer in this group of Bluetooth speakerphones by a noticeable margin, delivering louder and clearer sound on both sides of our phone calls, while doing an even better job than the iPhone 4 of filtering out ambient car noises. If you’re concerned that you won’t be able to hear your callers or be heard by them, this is the safest choice you can make to guarantee that both people in a call will be satisfied. Like BlueAnt’s S4, SuperTooth HD can also serve as an A2DP audio streaming device so that you can listen to music and audiobooks, too. There’s little doubt that it’s amongst the very best-sounding and capable visor-mounted speakerphones around—appropriate given its high price.

Another major feature of SuperTooth HD is the marquee addition to the device—but one that’s not as awesome as it initially appears to be on the surface. SuperTooth has partnered with a company called Dial2Do to offer a collection of voice-to-text options unlike anything on the rival products: you press the envelope button on the SuperTooth HD unit, it dials a telephone number, and you then say “Send a Text,” “Facebook,” “Send an Email,” or “Twitter.” Dial2Do’s service then records whatever you say, transforms your words into text, and sends the text through any of those services. In our tests, it worked remarkably well for brief messages, missing only the occasional word, and generally attached the original audio sample so that the recipient could hear what was said.

As nice as this feature is, it comes with strings attached. First, the Dial2Do service is only provided as a trial along with the SuperTooth HD unit—supposedly six months, said the package, but actually a year after we registered the unit with an included code. The basic service costs $40 per year, with a Pro version adding additional services for $60 per year. Second, in order to send e-mails and texts, or to do Facebook and Twitter posts, you need to use a Dial2Do web site to manually add contacts and services; there’s no iPhone app to handle contact or other setup issues automatically. SuperTooth has developed Android and Blackberry apps for Dial2Do, and an iPhone version’s supposedly forthcoming, but not here yet. Third and most trivially, a feature that’s designed to let you listen to your Twitter feed and an e-mail inbox presents the messages with lifeless text-to-speech that was difficult to make out and almost muddled. In sum, SuperTooth HD can indeed pull off all of these things, but it does a better job of sending text than reading it, and then, you’ll have to start paying for the service at some point in the future. We’d never shell out ongoing service fees for a service like this, but perhaps people with long commutes and strong needs to tweet or Facebook may feel otherwise.

There’s another minor issue that isn’t a showstopper, but really could stand to be fixed in a post-release firmware update. When the SuperTooth HD is turned on for the first time, you’re given a choice between British and American English—picking the latter switches to a female voice that’s charmless and all but unhappy. Hearing this voice is never as pleasant as it could be, and this is the only way in which SuperTooth HD lags behind the BlueAnt S4 and Plantronics K100, each of which does better with male or female voices.

Overall, SuperTooth HD is such a strong performer that it doesn’t need the Dial2Do functionality or a beautiful speaking voice in order to be worthy of a high recommendation—it performs so well as an iPhone speakerphone, and as a stereo Bluetooth music streaming device, that it’s worthy of consideration strictly on those merits. That having been said, though the Dial2Do-assisted functionality is a compelling addition to the product, the idea that your $129 purchase only gets you a trial of the service is a real disappointment, and though the duration of the trial isn’t bad, the ongoing fees aren’t in our view worth paying. The American English voice could also use an upgrade in the charm department, but it’s completely functional, and goes beyond what devices four or five years ago could have dreamed of offering. While it’s not perfect, SuperTooth HD is a great option if you’re looking for a high-quality speakerphone at a premium price; you can choose whether or not to enjoy the Dial2Do functionality as a short-lived extra.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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